Abstract
In a recent paper [arXiv:1206.4916] by T. Padmanabhan, it was argued that our universe provides an ideal setup to stress the issue that cosmic space is emergent as cosmic time progresses and that the expansion of the universe is due to the difference between the number of degrees of freedom on a holographic surface and the one in the emerged bulk. In this note following this proposal we obtain the Friedmann equation of a higher dimensional Friedmann-Robertson-Walker universe. By properly modifying the volume increase and the number of degrees of freedom on the holographic surface from the entropy formulas of black hole in the Gauss-Bonnet gravity and more general Lovelock gravity, we also get corresponding dynamical equations of the universe in those gravity theories.
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References
A.D. Sakharov, Vacuum quantum fluctuations in curved space and the theory of gravitation, Sov. Phys. Dokl. 12 (1968) 1040 [Dokl. Akad. Nauk Ser. Fiz. 177 (1967) 70] [Sov. Phys. Usp. 34 (1991)394] [Gen. Rel. Grav. 32 (2000) 365] [INSPIRE].
M. Visser, Sakharov’s induced gravity: A modern perspective, Mod. Phys. Lett. A 17 (2002) 977 [gr-qc/0204062] [INSPIRE].
T. Padmanabhan, Thermodynamical Aspects of Gravity: New insights, Rept. Prog. Phys. 73 (2010) 046901 [arXiv:0911.5004] [INSPIRE].
T. Jacobson, Thermodynamics of space-time: The Einstein equation of state, Phys. Rev. Lett. 75 (1995) 1260 [gr-qc/9504004] [INSPIRE].
T. Padmanabhan, A Physical Interpretation of Gravitational Field Equations, AIP Conf. Proc. 1241 (2010) 93 [arXiv:0911.1403] [INSPIRE].
T. Padmanabhan, Entropy density of spacetime and thermodynamic interpretation of field equations of gravity in any diffeomorphism invariant theory, arXiv:0903.1254 [INSPIRE].
E.P. Verlinde, On the Origin of Gravity and the Laws of Newton, JHEP 04 (2011) 029 [arXiv:1001.0785] [INSPIRE].
W.G. Unruh, Notes on black hole evaporation, Phys. Rev. D 14 (1976) 870 [INSPIRE].
T. Padmanabhan, Equipartition of energy in the horizon degrees of freedom and the emergence of gravity, Mod. Phys. Lett. A 25 (2010) 1129 [arXiv:0912.3165] [INSPIRE].
T. Padmanabhan, Gravitational entropy of static space-times and microscopic density of states, Class. Quant. Grav. 21 (2004) 4485 [gr-qc/0308070] [INSPIRE].
R.-G. Cai and S.P. Kim, First law of thermodynamics and Friedmann equations of Friedmann-Robertson-Walker universe, JHEP 02 (2005) 050 [hep-th/0501055] [INSPIRE].
R.-G. Cai, L.-M. Cao and Y.-P. Hu, Hawking Radiation of Apparent Horizon in a FRW Universe, Class. Quant. Grav. 26 (2009) 155018 [arXiv:0809.1554] [INSPIRE].
R.-G. Cai, L.-M. Cao and N. Ohta, Friedmann Equations from Entropic Force, Phys. Rev. D 81 (2010) 061501 [arXiv:1001.3470] [INSPIRE].
T. Padmanabhan, Emergence and Expansion of Cosmic Space as due to the Quest for Holographic Equipartition, arXiv:1206.4916 [INSPIRE].
R.-G. Cai, Gauss-Bonnet black holes in AdS spaces, Phys. Rev. D 65 (2002) 084014 [hep-th/0109133] [INSPIRE].
R.-G. Cai and Q. Guo, Gauss-Bonnet black holes in dS spaces, Phys. Rev. D 69 (2004) 104025 [hep-th/0311020] [INSPIRE].
R.-G. Cai, A note on thermodynamics of black holes in Lovelock gravity, Phys. Lett. B 582 (2004) 237 [hep-th/0311240] [INSPIRE].
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Cai, RG. Emergence of space and spacetime dynamics of Friedmann-Robertson-Walker universe. J. High Energ. Phys. 2012, 16 (2012). https://doi.org/10.1007/JHEP11(2012)016
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DOI: https://doi.org/10.1007/JHEP11(2012)016